"Family Business" is the 69th episode of the television series Star Trek: Deep Space Nine, the 23rd episode of the third season. It marks the first appearances of three recurring characters: Quark's mother Ishka, Captain Kasidy Yates, and Liquidator Brunt, FCA.

In Quark's, an agent named Brunt from the Ferengi Commerce Authority (FCA) - (their version of the IRS) - serves Quark with a Writ of Accountability for improper supervision of a family member. Quark and Rom's mother, Ishka, is charged with earning a profit – an illegal activity for Ferengi women. As the family's eldest male, Quark is held responsible. He and Rom return to their homeworld, Ferenginar, where Quark must convince Ishka to confess, as required by Ferengi law. The brothers arrive at their childhood home with Brunt, but Quark is not comfortable with seeing his mother again. They are surprised to find Ishka wearing clothes, which is also illegal for Ferengi women. Brunt tells Quark he has three days to get his mother to sign a confession, then leaves. Later, Ishka confirms over dinner that she broke Ferengi law by investing a portion of her monthly stipend from Quark, earning a meager three bars of latinum in the process. Still, she refuses to confess, which angers her oldest son.

In her room, Ishka reveals to Rom that she will not admit to being wrong – this is a matter of pride, and proof that she is just as capable of earning profit as a man. But Quark discovers that Ishka has actually been conducting business transactions under dozens of aliases all over the Ferengi Alliance, making much more than just three bars of latinum. Even if Quark sells everything he owns, he will be unable to pay back what his mother has earned. Quite simply, he's ruined.

Quark confronts Ishka, who accuses him of being jealous of her financial acumen – just like his deceased father. With that, an infuriated Quark decides to turn in Ishka to the FCA. Rom tries to stop him, but the conversation deteriorates into a brawl, after which Ishka declares that if Quark insists on reporting her secret transactions, then she won't stand in his way.

In the Tower of Commerce, Quark waits outside Brunt's office when Rom suddenly rushes in with the news that Ishka will split her profits with Quark, fifty-fifty. Seeing the entire affair in a different light, Quark hurries home to accept Ishka's offer. But when he arrives, Quark learns Rom made up the story, lying to both of them to force a conversation between the two. Alone with Quark Ishka tells him that, since he is her son, she will sign the confession and give back the money. Later, she pays her reparations to Brunt, and a relieved Quark says his good-byes and leaves. Now alone with Rom, Ishka reveals that she outsmarted Quark and the Ferengi government yet again – by giving up only a third of her profits.

The side plot of the episode involves Sisko meeting Yates as a romantic interest, which Sisko has discovered his son has told most of the station about.